Why do mountain residents live longer?

Is it somehow healthier to live in the mountains? That’s what a new study from Harvard University seems to say.Seven of the 10 counties that lead the nation in longest average life expectancy, 81.3 years, are located along the Continental Divide in Colorado. Four of these seven counties – Clear Creek, Grand, Eagle, and Summit – have ski areas (Loveland, Winter Park, Vail, and Breckenridge respectively).So, skiing would seem to be the explanation, right? Or at least the wealth that often goes with skiing. After all, can’t wealthier people afford better medical care?Maybe so, but healthy living and regular checkups alone don’t explain the high rankings. Consider the three other counties in Colorado that also lead the nation in longevity: Gilpin, which is where the smoke-filled casinos of Blackhawk and Central City are located; Jackson, better known as North Park, a ranching area that is among Colorado’s poorer places; and Park, partially the setting for the famous television series “South Park” and also location of the blue-collar Breckenridge suburbs of Fairplay and Alma.The only thing these places have in common, other than people long in the tooth, is thin air. The lowest point in any of them is in Eagle County, at the edge of Glenwood Canyon, where the elevation is about 6,000. Some principal towns among them range up to 9,000 and 10,000 feet.Also having the same longevity are three counties – two in Iowa, and one in Maryland – located slightly above sea level.Rounding out the nation’s top-40 places for life expectancies are:• Five more counties from mountainous areas of Southwest Colorado (San Miguel, Ouray, Mineral, Hinsdale, Gunnison, and Archuleta);• Five from Utah (Morgan, Summit, Washington, Cache and Rich), all but one in mountainous areas; • Four in Idaho (Blaine, Boise, Camas and Custer), all in mountainous areas. However, the mountainous areas of Idaho are sometimes lower than Denver.Compared to Eagle County’s life expectancy of 81.3 years, data showed life expectancy in Pitkin County to be 79.8 years. In contrast, Denver was at 75.9. The state’s lowest life expectancies were in three counties in the southwest: San Juan (Silverton), Montezuma (Cortez), and Dolores (Dove Creek).So, if skiing and money aren’t the fountain of youth, what could it be? Testimony to the value of pretty scenery? Sucking extra hard for a lung full of air?The short answer is that the Harvard researchers don’t know why, after analyzing national data from 1980 to 1999, mountain counties lead the nation in longevity. That was but a footnote to the broader study of longevity trends across the nation.In that macro study, the researchers found that wealth is not necessarily a predictor of who lives longest. The longest-lived group of people are Asian-American females in New Jersey. On the flip side, the nation’s shortest life expectancy is among Native American men in South Dakota and black men in urban areas, and more broadly rural counties in the South.Dr. Christopher Murray, the lead researcher, told reporters that shorter life expectancies are linked to tobacco use, alcohol, blood pressure, obesity, diet and physical inactivity. By reverse logic, mountain counties may have more physically active people who eat well and don’t smoke, he said. And indeed, Colorado – which ranked in the second tier of states, behind Hawaii, for life expectancy – has the nation’s lowest obesity rate, a relatively low smoking rate, and a relatively active lifestyle, observed Dr. Ned Calonge, Colorado’s chief medical officer. Still, none of this satisfactorily explains why Rocky Mountain counties top the nation in longevity. There are two theories. One can be called the theory of self-selection.When people get sick, particularly with chronic lung and air diseases, they tend to leave the high country for lower elevations in Grand Junction and Denver, Tucson and Phoenix, where medical facilities are generally better and the air has more oxygen. This is mostly anecdotal, although one study conducted in the early 1980s documented the migrations in Colorado.On the flip side, migrants who are healthier may be drawn to mountain counties. The ski towns have increasingly become places of gray hair. The above-60 age cohort, while still relatively small, was the fastest-growing population segment in the 1990s.A second theory is advanced by Dr. Benjamin Honigman, director of the Colorado Center for Study of Altitude Medicine and Physiology. That theory holds that people who have lived here at higher elevations for a long time develop some kind of protective effect that yields stronger lungs and hearts. That has been proven in populations who have lived hundreds or thousands of years in high elevations. Tibetans, for example, have lived at locations of 12,000 feet and even higher. But that theory lacks supporting evidence, says Honigman. “There isn’t much known about longevity and altitude,” he says.Honigman hopes to find money to study the connection between thin air and health.Allen Best can be reached at bestallen@earthlink.net.